
Originally Posted by
rspears
Em,
I always drill a small, nominal 1/8" hole in the thermostat disk to let the air bleed out of the engine while filling the system. Without the hole it is too easy to get air trapped at the thermostat housing, and the thermostat won't open until the bi-metal spring is surrounded by coolant. Catch 22, and very frustrating. Pull your stat, drill a hole and then listen as you fill and you'll hear the air bubbling out through the hole. Works like a charm, and provides the added benefit of a very slight flow through the closed stat to get the warm water circulating faster.
Yep. It’s pretty sad.
Dead!